Devices and methods for bone stabilization

ABSTRACT

A compression stabilized prosthetic socket for a patient having an amputated limb and a remaining portion includes a first socket portion for contacting a patient&#39;s remaining portion of a limb, and a second socket portion for attachment of a prosthetic device. The first socket portion has compression portions having a radius for compressing portions of the patient&#39;s remaining portion of a limb, and relief portions receiving any portions of the patient&#39;s remaining limb which bulge upon the compression applied by the compression portions. The relief portions may be formed as openings or as enlarged radius portions.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims the benefit ofpriority from U.S. patent application Ser. No. 12/945,876, filed Nov.14, 2010 which in turn is a continuation-in-part of, and claims thebenefit of priority from U.S. patent application Ser. No. 12/792,728,filed Jun. 2, 2010 which in turn is a continuation-in-part of, andclaims the benefit of priority from U.S. patent application Ser. No.12/380,861, filed Mar. 4, 2009, which in turn claims benefit of U.S.Provisional Patent Application No. 61/068,263 filed Mar. 4, 2008, allfour of which such applications are incorporated by reference herein.

FIELD OF INVENTION

The present invention relates to the prosthetic limbs worn by upper orlower limb amputees and in particular to the portion of a limbprosthesis that is in direct contact with the user's skin.

DESCRIPTION OF THE RELATED ART Definitions of Terms

Socket—is that part of a prosthesis in direct contact with the user'sskin. The word Socket usually implies a traditional socket that isessentially circular in cross section. A traditional prosthesis consistsof an inner socket to interface with the user's skin and an outer socketover it that continues to incorporate the mechanisms that comprise thenext distal structure which may be a joint or a device to function as afoot or gripping device. The inner and outer sockets may be separatestructures or may be unitary consisting of a single unit.

Interface—is often used as a synonym for socket, but is more oftenreserved for socket-like structures that have openings in the outersocket and occasionally in both the outer and inner sockets.

Cast—is a thin layer of wet plaster impregnated gauze wrapped around aresidual limb and the surrounding body parts and then permitted toharden to reproduce the shape of the limb. While the plaster ishardening, pressure from the hands of the plaster technician oftenmodifies the shape to accommodate the underlying boney anatomy.

Positive Model—is the plaster model that results from filling a castwith plaster or similar material. Modifications by adding andsubtracting plaster are made to this model before its outer surface isused to define the shape of the user's socket or interface.

Check Socket—is a temporary socket made over the model and used to testwhether the modifications have had the desired effect on the fit of theresulting socket.

Channel—is used here to describe a longitudinal area where the wall of asocket is depressed inward as close to the underlying skeletalstructures as is comfortable.

Relief Area—is the region in a socket system between two channels oraround or near a compressed area which provides a place for thedisplaced tissue to migrate.

Lost Motion—is the motion of the skeletal structures with respect to theprosthetic interface when force is applied between the two as wouldoccur as an amputee tries to move the prosthesis as a whole. In atraditional socket lost motion occurs when the bone moves toward thesocket wall a substantial distance before imparting force to the wall.

Compression Bar—is a long flat bar typically a little shorter than theshaft of the remaining long bone(s). The width of the bar is usuallyabout ten percent of the circumference of the remaining limb.

Optimal Tissue Compression—is compression of the tissue against thesocket wall such that lost motion is minimized without causingdiscomfort to the user.

High-fidelity Interface or device—is the name given to the socket orinterface that utilizes compression stabilization as the basis for itsfunction and physical structure.

BACKGROUND OF THE INVENTION

Historically the prosthetic user interface has been a cylindrical socketthat merely surrounds the remaining limb part with some contouring ofthe proximal brim so that it will accommodate the shape of the nextproximal joint or body part. Typically this socket is made by taking aplaster cast over the limb and filling it with plaster to form apositive model of the limb. Minor changes are made to this shape torelieve boney prominences. When this model is used to create a socket bylaminating or thermoforming a layer of plastic there over, the resultingsocket mainly encapsulates the limb part. Conventionally, nomodification of the traditional model is done. This opportunity tospecifically enhance the resulting structure's ability to impart desiredmotion to the complete prosthesis, and to prevent undesired motion fromoccurring, has been overlooked, even though these are the most importantfunctions of the interface. The traditional encapsulating or closedvolume socket merely contains the soft tissue but does little or nothingto prevent lost motion between the socket and the underlying skeletalstructure.

Some improvements have been made in the traditional interface. Inparticular, many technicians replace the fully encapsulating outersocket with a frame having one or more openings. This change isaccompanied by making the inner socket of a flexible material. Theresulting frame-style design usually is more comfortable. New materialssuch as carbon fiber composites add rigidity where needed especially inopen frame designs. New flexible materials allow the socket wall to flexin other areas for comfort. Even when these newer flexible materials areused, the soft liner still fully encapsulates the remaining limb astraditionally done, and thus provides a compressive or elastic force toall of the limb's soft tissue.

Conventional laminations over a plaster model work best when thesurfaces of the model are convex facing outward, following the generalcontours of the outside surface of the limb.

SUMMARY OF THE INVENTION

In a preferred embodiment of the invention a mold (negative model) ismade by making a cast of a remaining limb on which a prosthesis will beused. From the mold/cast, a positive model is made of the remaininglimb. There are deep channels formed in the positive model, which are acause of excessive thickness in these areas when conventional laminationprocedures are used. Where the areas between the channels are to be leftopen, however, the model may be brought almost flush with the edges ofthe compressed areas. This alteration permits a much strongerlamination. Another technique to strengthen the resulting struts is tocorrugate the compression channel area to create a resistance to flexupon lamination.

When taking a cast of the area above the knee, prosthetists are oftenassisted by using jigs especially to establish the shape of the brimarea for transfemoral sockets. In the new socket technology of thisinvention one may also use a jig to assist in achieving an optimal castof the area above the knee.

Preventing Lost Motion

In one embodiment, a basis of this invention stems from a simpleobservation using a procedure such as described below. A person holdshis/her arm in a fixed position so that an experimenter cannot easilymove the arm side to side. The experimenter then pushes with a finger onthe fleshy area over the long bone of the upper arm. Typically, thefinger will push into the soft tissue a centimeter or more before itcompresses the tissue against the bone and no further motion is possiblewithout the subject moving. During compression, tissue moves aside awayfrom the area of compression. From the inventor's knowledge, no priordesigns have specifically allowed for the displacement of tissue as arequirement for achieving stability even if local compressed areasexist. For a long bone to be fully stabilized with respect to theprosthetic interface, compression must be applied in a specific way.Typically three or four channels are created in the socket along theentire length of the bone except at the very ends. Accordingly, thechannels extend proximate to ends of the bone, e.g. at least eighty andmore preferably at least ninety percent of the existing longest bone inthe existing limb. The inner surfaces of these channels compress thetissue against the long bone until little further motion is possible.For this compression to be effective, there must be a longitudinalrelief area between each pair of channels. The channels and the reliefareas are two key elements of a preferred embodiment of the inventionand both must be present for optimal performance. In a more preferredembodiment, a third key element is that at least three channels areneeded to impart full stability.

Creating the Compression Stabilized Socket Interface

The traditional prosthetic socket is created by taking a cast, making apositive model, and modifying the model to create a form for shaping afinal socket interface. An important element of a preferred embodimentof this invention is the use of the traditional sequence in a new way.Three to four compression bars are made prior to taking the cast. Theseare tested by spacing them appropriately around the remaining limb andpushing in. Care is given to both the physical and anatomical structuresof the limb in determining proper placement. In the case of the upperlimb, specifically the humeral level in which positional precision andlifting capacity take precedent, the locations of these compression barsare biased toward stabilization in flexion and abduction, the two mostcommon functional motions utilized, resulting in narrower relief windowsin the anterior and lateral areas of the socket. The length, width, andcurvature of the bars are adjusted until they lock the underlying bonein place when equal pressure is applied to the bars. The individual barsare checked to see if they rock end-to-end when pressure is shifted inwhich case a change in shape is indicated. Before taking the cast, theprosthetist must decide how to arrange the bars around the limb so thatforces are optimally transmitted when the resulting interface is used.The underlying location of nerves and other structures will determinethe exact angular orientation of the bars and may determine the optimumnumber of bars to use.

The cast is taken by applying a loose wrap of wet elastic castingplaster. The bars are then placed in the pre-planned positions, pressedinto the elastic wrap and soft tissue by hand or with a casting jig withsufficient force to impart substantial compression on the limb and heldin place while the plaster sets. It is important for the wrap to be ableto stretch so that the displaced tissue has somewhere to go. Even in thebest of circumstances, the plaster will prevent the bars from achievingoptimal penetration. This is corrected during the cast rectificationstage. Before, during or after the channels in the plaster and thebulges in between are sufficiently set, the proximal parts of the castare taken in the usual manner. However, some areas in this secondaryarea of the wrap may also need to be compressed by the fingers of thecast taker to create additional areas of pre-compression.

For taking a femoral level cast, the distances and forces needed aregreater and a bar-location jig is of great help. This jig is an integralpart of the invention for femoral casting and femoral interface socketsand could also be used if desired for humeral casting. The jig consistsof two or more stiff “d”- or “c”-shaped rings with the flattened surfaceof the d-rings or the open surface of the c-rings positioned to themedial or inside area next to the midline of the body or the oppositeleg if present. These rings are large enough to allow some space insidethe rings when they are placed around the limb. Each ring can accept asingle screw attachment or plurality of screw attachments. Eachattachment can be oriented azimuthally around the ring and then lockedin place. Each attachment has a screw or screws aimed at the center ofthe ring capable of applying force to one of the channel-forming bars.In addition the attachments are open on one of the sides that faceparallel to the limb in the B-ring design. This opening permits theprosthetist to remove a single pair of attachments and the underlyingbar after the preliminary setup described below. The c-ring designinherently already has this opening. Small snap-in pockets along theoutside of each bar and the fact that the screw ends are sphericalprevent slipping once the bars are in place. In the ideal embodiment thepockets have a restriction at the opening that makes the attachment ofthe screw ends act like pop beads to hold the screw end to the bar. In atypical cast taking at the femoral level, two rings are used and eachhas four attachments oriented approximately ninety degrees apart. In thedesign utilizing two screws for each compression bar, the attachmentscrews are placed in pockets on the bars about twenty percent of thelength of the bar in from the end. Before the cast is taken theprosthetist experiments and selects the best length and width for eachbar and the optimal location. To speed application during the actualcast taking, all positions are marked with the anticipated extracircumference of the added plaster wrap accounted for.

After the cast has been filled to create a positive model, the plastertechnician will usually need to deepen the channels before pulling athermoformed check socket out of transparent plastic. If a solid-bodiedcheck socket will be utilized, then additional plaster must be addedover the relief areas of the positive model to allow sufficientdisplacement of soft tissue into the check socket's relief areas.Usually several check sockets will be needed. As each is applied to theuser, the fit and stability of the check socket is evaluated. The colorof the tissue will tell the experienced practitioner where too muchcompression is being applied and where there is too little. In additionsubstantial forces should be applied in all directions to ensure thatthe stabilization is optimal. Since the compression stabilized interfacedesign requires that the areas between channels be left free orsufficiently relieved for tissue movement, there is good reason forleaving these areas fully open in the check socket unless anencapsulating or solid-body interface is desired. The user can then morereadily perspire and dissipate excess body heat. With three or more longopenings in the socket wall, a traditional cloth laminate is usuallyreplaced by a stiff, strong carbon fiber reinforced laminate in the formof a frame.

Usually a temporary assembly of the distal prosthetic components isadded to the final check socket and tested before the shape of the checksocket is approved for creating the definitive prosthesis. For approval,the interface must transmit force and motion to the prosthesis in everydirection that the user will require with minimal lost motion betweenthe interface and the rest of the prosthesis.

In a presently preferred embodiment of the invention, there is a limbinterface device. The limb interface device has either an encapsulatingdesign with adequate soft tissue reliefs or an open cage or strut-typeconfiguration of rigid, semi-rigid or dynamically adjustable strutsappropriately contoured to a patient's residual limb. The open cage orstrut-type configuration contains windows through which soft tissue canflow out of the interface confines.

The limb interface device may have any of various prosthetic componentsattached to it to provide an upper or lower extremity prosthesisextending from the distal end of the interface device. The regions ofcompression in both the encapsulating and strut-type embodiments areconfigured and aligned in such a way as to transfer skeletal movement asefficiently as possible such that interface response to volitionalmovement and interface stability are maximized. Optionally, stabilizersor other devices may be attached to a proximal end of the limb interfacedevice.

In the open cage or strut-type configuration, the strut edges can beconfigured such that they are either flexible enough or shapedappropriately to mitigate edge pressure and hence soft tissue stress, ora material can be fitted to the struts such that it extends just beyondthe border of the rigid or semi-rigid edge and provides a more gradualtransition of pressure at this location.

In another preferred embodiment, the interface device may have theability to alter the stiffness of the strut assembly itself on demand orautomatically in response to applied loads such that edge pressure oroverall strut compression is varied appropriately to prevent skin orunderlying soft tissue damage. Finally, an inner, highly flexiblemembrane may be utilized that encapsulates the entirety of the limb andis placed between the strut assembly and the limb yet still allowssufficient soft tissue flow beyond the confines of the strut assemblysuch that edge pressure on the soft tissue and redundant intrinsicskeletal motion are minimized.

Although embodiments of the present interface assembly finds particularapplication with prosthetic limbs, it is also to be appreciated that theinterface assembly may be used in other applications such as orthoticsor other interface applications involving the human body.

Still other objects, advantages and constructions of the presentinvention, among various considered improvements and modifications, willbecome apparent from the detailed description provided hereinafter. Itshould be understood that the detailed description and specificexamples, while indicating a presently preferred embodiment of theinvention, are intended for purposes of illustration only and are notintended to limit the scope of the invention.

In some parts of the orthotic and prosthetic industry, cast taking hasbeen replaced by laser scanning of the residual limb and the creation ofa virtual solid model. It is anticipated that simple algorithms can becreated to permit insertion of channels and bulges in a virtual modelsuch that the area inside the virtual wall of any cross section of theresidual limb would remain the same. Such an algorithm automaticallycreates appropriate bulges when the technician moves a portion of thewall toward the skeletal structures in the virtual model. Principles ofthe embodiments of the invention are not changed when the model forcreating the definitive interface structure is based on a plaster castor on a virtual model produced with software.

In a preferred embodiment, there is a prosthetic socket which preventslost motion between an amputee's remaining limb and the prosthesis byselectively compressing tissue against the bone in some areas whileproviding relief in other areas so that displaced tissue is accommodatedwhen forces are applied between the bone and the interface. Additionalembodiments of the invention include methods for creating the new socketdesign.

It is an object of various embodiments of the present invention toprovide a prosthetic interface within which the individual's upper orlower extremity residual limb part is captured with greater stabilitythan in known prior art.

It is a further object of various embodiments of the invention toprovide a mechanism to selectively compress the soft tissue between theresidual limb's skeletal structure and socket structures to minimizelost motion when the skeletal structures of the residual limb move withrespect to the socket and attached prosthesis.

It is a further object of various embodiments of the present inventionto provide a plurality of areas of compression parallel to the long axisof the major bone or bones of the residual anatomy.

It is a further object of various embodiments of the present inventionto provide open or low-compression relief areas between said areas ofcompression so that said compression is not impeded by the inability ofthe underlying tissue to flow or migrate sideways.

It is a further object of various embodiments of the present inventionto provide a method for taking a cast of the residual limb that resultsin an approximation of the desired final shape of the socket interface.

It is a further object of various embodiments of the present inventionto create areas of compression in a plaster cast parallel to the longaxis of the residual limb during the process of cast taking with bulgesin between that will define areas of relief in the complete prostheticinterface.

It is a further object of various embodiments of the present inventionto provide check sockets where areas of relief are created by leavingthe socket wall completely open or are large enough in the encapsulatingversion to allow for sufficient soft tissue displacement.

It is a further object of various embodiments of the present inventionto provide definitive prosthetic interfaces where areas of compression,both with respect to the underlying bone as well as with respect to thearea of compression just proximal to the bulging soft tissue, tostabilize the longitudinal motion of the prosthesis with respect to theskeletal anatomy thus aiding in suspension and weight bearing.

It is a further object of various embodiments of the present inventionto provide definitive prosthetic sockets where a soft liner covers thelimb but is stabilized by a frame there over with the frame performingthe functions of a traditional outer socket. (If such a liner is used,the model over which it is formed must have bulges between thecompression channels large enough to create a liner with little or notissue compression in the areas between the areas of compression.)

It is a further object of various embodiments of the invention toprovide areas into or through which a significant amount of soft tissueof the said limb can flow freely, without restriction or with minimalrestriction so as to permit sufficient soft tissue flow away from areasof compression along the shaft of the bone or bones in theaforementioned areas of high compression.

It is a further object of various embodiments of the present inventionto take advantage of the anatomical response such that tissue can becompressed against bone just so far before further motion is impeded ifthere is room for the displaced tissue to move out of the way.

It is a further object of various embodiments of the present inventionto create prosthetic sockets with longitudinal grooves alternated withareas sufficiently open that the displaced tissue suffers nocompression.

It is a further object of various embodiments of the present inventionto create sockets that have three or more compression channels so thatlost motion is prevented in all directions.

It is a further object of various embodiments of the present inventionto shape the interior surfaces of the grooves such that when theprosthesis is loaded the local pressure along the length of the bone isequal without excessive pressure at the ends.

It is a further object of various embodiments of the present inventionto provide means for creating a prosthetic interface by applying aplurality of bars or a loose plaster wrap during the cast takingprocedure.

It is a further object of various embodiments of the present inventionto provide a jig for holding the bars in position during cast taking

It is a further object of various embodiments of the present inventionto provide a jig having two or more rings larger in diameter than thelimb. Each ring has a single or plurality of snap-in-place screwholder(s) with adjustment screws oriented so the axis of the screwpasses through the center of the ring.

It is a further object of various embodiments of the present inventionto provide screw holders that are applied to the ring by moving parallelto the axis of the ring. This feature permits a bar screw holder or abar and two screw holders to be removed from a pair of rings as a unit.

It is a further object of various embodiments of the present inventionto provide adjustment screws with spherical ends.

It is a further object of various embodiments of the present inventionto provide a snap-in socket or plurality of snap-in sockets along thecenter line of the outside of each bar which accept the spheres on theadjustment screws.

It is a further object of various embodiments of the present inventionto provide bars with center sections that telescope so bar length can beadjusted as well as to offer different length bars to be snapped inplace depending on the application.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view from an anterior position of a transhumeralhigh-fidelity interface device in accordance with a first preferredembodiment of the invention, where the device has an open cage orstrut-type structure;

FIG. 2 is a perspective view from an anterior position of a transhumeralhigh-fidelity interface device in accordance with a second preferredembodiment of the invention, where the device has a closed structure;

FIG. 3 is a cutaway view from the top of the interface device of FIG. 2,showing an interior thereof;

FIG. 4 is a view of the device of FIG. 1 on a patient's left arm;

FIG. 5 is a perspective view from a medial position of a transradialhigh-fidelity radial interface device as a closed structure;

FIG. 6 is a perspective view from an anterior position of a transfemoralhigh-fidelity interface device in accordance with a fourth embodiment,where the device has a closed structure;

FIGS. 7 a, 7 b show an example of a jig design utilized for transfemoralcast taking in preparation for the creation of a transfemoralhigh-fidelity interface;

FIGS. 8 a and 8 b show the anterior and posterior perspectives of anexemplary transfemoral high-fidelity interface attached to prostheticcomponents;

FIG. 9 is a drawing showing a casting

FIG. 10 is a drawing showing a mold formed from the casting;

FIG. 11 is a flow chart showing steps in a process of an embodiment ofthe invention for making a high-fidelity interface for a prosthesis andlimb, preferably a lower limb; and

FIG. 12 is a flow chart showing steps in an alternate process of anotherembodiment of the invention for making a high-fidelity interface for aprosthesis and limb, preferably an upper limb.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

As shown in FIG. 1, a the transhumeral open-cage interface embodiment,there is an upper portion 1, which has both an anterior stabilizer 2 anda posterior stabilizer 3 and which extends in a proximal (in this casetoward a patient's shoulder) and medial (toward a patient's midline)direction from a lower portion 4 to stabilize the interface on apatient's body. Although stabilizers 2 and 3 are not required, they arerecommended to impart or enhance rotational stability. The lower portion4 (below line 5) has an open-cage structure. Dashed horizontal line 5demarcates the upper and lower portions. The lower portion 4 of thisopen-cage embodiment has multiple, e.g. three or four struts 6, whichlook like fingers that extend along the long axis of the residual limband are designed to partially encompass the residual limb, allowing softtissue to flow through windows 7.

As shown in FIG. 2, a transhumeral solid-body interface embodiment,there is an upper portion 1 a, which has both an anterior stabilizer 2 aand a posterior stabilizer 3 a and which extends in a proximal (in thiscase toward the shoulder) and medial (toward the midline) direction fromlower portion 8 to stabilize the interface on the body. Althoughstabilizers 2 a and 3 a are not required, they are recommended to impartor enhance rotational stability. In this embodiment, lower portion 8 isa solid body structure. A dashed horizontal line 5 a demarcates theupper and lower portions. The lower portion of this solid-bodyembodiment has multiple, e.g. three or four, compression areas 9 andsoft tissue relief areas 10 that extend along the long axis of theresidual limb and are arranged circumferentially in an alternatingcompression-relief pattern as shown. Soft tissue relief areas 10 musthave a volume sufficient to cleave displaced skin and other tissue fromcompression applied by compression areas 9.

In FIG. 3, an interior of the transhumeral solid-body interfaceembodiment is shown, with alternating compression areas 9 and reliefareas 10 indicated.

In FIG. 4, a patient is shown wearing a transhumeral open-cage interfaceembodiment such as that of FIG. 1 with a suspension liner 30 of minimalthickness or of sufficient stretch to minimally restrict soft tissueflow through the relief windows. Struts 6 providing soft tissuecompression and windows 7 allowing soft tissue flow are indicated.

In FIG. 5, a transradial solid-body interface is shown. In thisembodiment, there is an upper portion 11, which comprises the area ofthe interface proximal to olecranon 12 and cubital fold 13. A lowerportion 14 has multiple, e.g. three or four, compression areas 15 andsoft tissue relief areas 16 that extend along the long axis of theresidual limb and are arranged circumferentially in an alternatingcompression-relief pattern as shown.

In FIG. 6, a transfemoral solid-body interface is shown. This embodimenthas multiple, e.g., three or four, compression areas 17 and soft tissuerelief areas 18 that extend along the long axis of the residual limb andare arranged circumferentially in an alternating compression-reliefpattern as shown.

In FIGS. 7 a and 7 b, there is shown a tool for use in imaging (andparticularly helpful for the lower limb), which tool optionally may beused with various embodiments of the invention. Imaging is a process torender a model of the limb using plaster bandage, laser scanning orother such technique. Imaging of a limb under compression may be done tocreate the model. This tool is essentially a connected set of adjustablebars attached to screws which in turn are connected to a circumferentialor partially circumferential ring that allows this tool to be placedover the limb either before, during or after the imaging process andthat applies the appropriate compression to the soft tissues of the limbin desired target areas while allowing redundant soft tissue to flowthrough the areas between the struts unhindered.

More specifically, the jig consists of a multiplicity of paddles 101 forpushing inward against the limb remnant of an amputee. For mostpurposes, four paddles preferably are used. For the configuration shown,eight sectors 110 are assembled into two rings. Eight screws are used atlocations 111 to assemble the rings.

In FIG. 7 b, a screw (not shown) is inserted into clearance hole 112 tosecure the turnbuckle holder 108 to the sector 110. Until the screw istight, the holder is free to rotate with respect to the sector. Theturnbuckle rod 106 is threaded with an eyelet 113 on the far end toconnect to paddle holder 105. A pin attaching these two parts isinserted into hole 114. Paddles 101 each have a channel 103 into which aslider 102 is captured. This slider has two threaded bosses 104 whichare secured to paddle holder 105 by nuts (not shown). By loosening thesetwo nuts the slider may be repositioned along the paddle.

To adjust the position of the paddle, a threaded wheel 107 is turned. Inthe configuration shown, there are a total of eight turnbuckleassemblies to position the paddles in contact with the amputee's limb.Preferably, the paddles are made from a rigid, inexpensive plastic thatcan be trimmed to a width and length suitable to the individual amputeefitting. All of the other components are preferably reusable.

As shown in FIGS. 8 a (an anterior perspective) and 8 b (a posteriorperspective), an exemplary prosthetic component set 22 is attached toone device 23. Various prosthetic components may be attached to thedevice by any one of various methods currently available or available inthe future. The device may have at a proximal end any one of varioussupport structures known in the art or developed in the future.

In a method in accordance with an embodiment of the invention, aninterface device with open-cage or strut-type is fitted onto a person.

First, it is determined whether a patient needs a transradial (radiallevel) device, a transhumeral (humeral level) device, a transtibial(tibial level) device or a transfemoral (femoral level) device. Thepatient or prosthetist may select a closed device or an open cagestrut-type high-fidelity device.

Second, the patient's limb radius is determined at one or morelocations. Third, the device is essentially crimped during modificationor creation of the device until sufficient compression from the at restradius of the patient's limb at the cage or strut region of the deviceis at a desired amount. The desired amount of compression will depend inpart on the patient's bone size, body fat, and other tissue parametersat the area of the cage or strut. The compression generally is at least20% or at least 30% from the at rest radius of the limb. Typically,compression will be from 20% to 70% or 30% to 70%. The amount ofcompression is sufficient such that there is minimum redundant tissuebetween the maximum point of compression and the target bone containedwithin the interface such that motion capture of the bone is maximizedwhile retaining sufficient comfort to allow the wearer to withstand thecompression for a useable amount of time and to ensure adequate bloodflow over time, which can be ascertained through the use of a bloodperfusion sensor and monitor. The blood perfusion sensor can be utilizedduring casting, diagnostic interface assessment or in the definitivesocket.

However, compression can be lower than 20% or higher than 70% dependingupon bone size, body fat and other tissue parameters, and theprosthetician and/or physician will use the blood perfusion sensor andmonitor and make a determination of the safety and effectiveness of theparticular amount of compression for the particular patient.

Fourth, the modified or rectified high-fidelity device with an innerradius or inner radii of size that can be fit over the distal (free) endof the patient's limb (for fitting with a prosthesis) is selected, andapplied to the patient's limb, e.g., by sliding onto the limb.

Creation and Fabrication of High-Fidelity Interface

In a method in accordance with an embodiment of the invention, aninterface device with open-cage (strut-type) or solid-body configurationis fitted onto a person.

First, it is determined whether a patient needs a wrist disarticulationdevice, a transradial device, a transhumeral device, a symes device, atranstibial device, a knee disarticulation device, a transfemoral deviceor a hip disarticulation device. The patient or prosthetist may select aclosed or open cage strut-type high-fidelity device as disclosed herein.

Second, the patient's limb radius is determined at one or more locationsalong the limb where the interface device will be fit.

Third, the interface is created using one of several different methods,all of which require modification by the prosthetist to complete fittingof such a final socket.

One method commonly employed is to cast the patient's limb utilizing aplaster bandage. This casting allows the prosthetist or clinician to addcompression forces to the plaster wrap and hence to the limb in thetarget areas that will hold this compression and allow for subsequenttissue relief between these compression areas as the plaster sets.

The cast, which will function as a negative model or mold, is removedand filled with liquid plaster.

The liquid plaster is allowed to set in the mold.

Once the liquid plaster has solidified, the plaster bandage (mold)surrounding the solid (positive) model is removed. The positive model isnow revealed to which the prosthetist or clinician applies additionalcompression to the target areas by carving directly on the model.Carving on the positive model creates a pressure or compression point onthe target areas because the “negative” model (the socket being moldedfrom the positive model) will now have a larger inwardly facingcompression area.

Another way to generate the limb shape to be modified is to use ascanner to obtain the image shape and then modify the digital imageaccordingly using well known software, e.g., on a computer such as alaptop. This digital model (as modified to apply targeted compressionand relief) can then be sent to a carver or 3 d printer to generate aphysical positive model over which a negative model (mold) can becreated for fitting or additional fabrication.

In order to determine appropriate compression levels, the device isessentially crimped during modification or creation of the device untilsufficient compression from the at rest radius of the patient's limb atthe cage or strut region of the device is at a desired amount. Thedesired amount of compression will depend in part on the patient's bonesize, body fat, and other tissue parameters at the area of the cage orstrut. The compression generally is at least 20% from the at rest radiusof the limb. Typically, compression will be from 20% to 70%, or at least30% to 70%. For certain patients, such as very muscular, or those havingcalcification, the minimum compression to achieve the advantages of theinventive method may be a little below the above minimum ranges, and forcertain patients, such as obese patients or others with extremely fleshyskin, a higher than 70% compression may be appropriate. However, comfortand medical safety can dictate the final appropriate amount ofcompression for any particular patient.

The amount of compression is sufficient such that there is minimumredundant tissue between the maximum point of compression and the targetbone contained within the interface such that motion capture of the boneis maximized while retaining sufficient comfort to allow the wearer towithstand the compression for a useable amount of time.

Fourth, the decision is made whether a diagnostic interface (transparentthermoplastic socket for analysis of fit and function prior to creatingthe definitive model) or a definitive interface, typically consisting ofa laminated framework, is to be created.

Over the now modified or crimped model, in order to create thediagnostic interface, a thermoplastic material is heated and draped orblister-formed, preferably under vacuum, to render a new negative model.Once the thermoplastic has cooled and become rigid, the plaster is thenremoved from within the thermoplastic interface and the interface istrimmed and smoothed and is of sufficient stiffness and transparency toallow the clinician to don it on the patient and judge the fit andpressures acting on the limb. This model can be removed from thepatient's limb and trimmed or heated to change its boundaries orperimeter and shape, including the amount of compression or relief thatis applied to the limb based on what is observed and comments from thewearer.

In order to create the definitive interface, an acrylic laminate (withor without stiffeners such as carbon fiber, Kevlar®, i.e., para-aramidsynthetic fiber, etc.) or similar can be vacuum formed directly over themodel or in the case of a frame style interface with a flexible linerand rigid frame, over an inner flexible liner that has been previouslyvacuum-formed over the same model.

The now compressed negative socket, whether in diagnostic or definitiveform can be donned by either a push-in or pull-in method, with thelatter being preferred due to the high levels of compression applied tothe limb. This compression imparts friction on the skin during donningand hence makes it more difficult to get all the limb tissue down in theinterface unless a donning sock or similar is used to pull the tissuein. The pull-in method utilizes a donning sock or similar such devicethat surrounds the limb and is pulled through a distal aperture at thedistal end or bottom of the interface. As the wearer pulls down on theend of the donning sock and pulls it through the aperture, the limb ispulled down into the interface until fully seated.

In FIG. 9, an example of a casting 240, e.g., for an upper limb, isshown.

In FIG. 10, a socket 202 having compression regions 209 and reliefregions 210 is shown on a patient's limb, e.g., an upper limb.

FIG. 11 is a flow chart showing steps in a process of an embodiment ofthe invention for making a high-fidelity interface for a prosthesis andlimb, preferably a lower limb, the lower limbs being the ones that willbe bearing weight of the wearer's body; and

FIG. 12 is a flow chart showing steps in an alternate process of anotherembodiment of the invention for making a high-fidelity interface for aprosthesis and limb, preferably an upper limb.

In FIG. 11, in a step 221, a technician will locate biomechanically,anatomically and physiologically appropriate location of compressionbars to be applied to an upper limb during casting or scanning such thatthere are alternating fields of compression and relief arrangedlongitudinally along shaft of long bone.

In step 222, a technician will, if casting, preferably use a casting jigas shown in FIG. 7 a or 7 b both before and after the plaster bandage isapplied to the limb in order to identify the locations described aboveand to apply appropriate compression to the limb underweight bearingconditions after the plaster wrap is applied respectively. If scanning,the technician will identify locations for compression bars such thatthey are retained in the modification software after scan is complete.

In step 223, a technician will create positive model from negative modelcreated above and modify such that the longitudinal compression areascorrespond to at least a 20% (or 30%) (up to 70%) diameter reduction ascompared to the uncompressed measurement if anatomically and physicallyappropriate. In some cases, compression below 20% or above 70% may beacceptable.

In step 224, a technician will create a diagnostic, negative model fromthe positive model above including longitudinally extending compressionregions corresponding to the amount of compression determined above, andrelief regions adjacent and in between the compression regions forreceiving at least a volume of the patient's fleshy portions on theremaining limb that are to be displaced by the compression regions. Therelief/release regions can be enclosed or completely open provided thereis minimal restriction to soft tissue flow.

In step 225, which is optional, one preferably will put on al sock orsleeve to facilitate donning by pulling the limb down into the socketmore completely.

In the process of FIG. 12, in step 231, a technician will locatebiomechanically, anatomically and physiologically appropriate locationof compression bars to be applied to (lower) limb during casting orscanning such that there are alternating fields of compression andrelief arranged longitudinally along shaft of long bone.

In step 232, the technician will, if casting, apply a plaster bandage tolimb and over this apply compression bars in the predetermined locationsabove. If scanning, the technician will identify locations forcompression bars such that they are retained in the modificationsoftware after scan is complete.

In step 233, the technician will, create positive model from negativemodel created above and modify such that the longitudinal compressionareas correspond to at least a 20% (or 30%) (up to 70%) diameterreduction as compared to the uncompressed measurement if anatomicallyand physically appropriate. In some cases, compression below 20% orabove 70% may be acceptable.

In step 234, the technician will create a diagnostic, negative modelfrom the positive model above including longitudinally extendingcompression regions corresponding to the amount of compressiondetermined above, and relief regions adjacent and in between thecompression regions for receiving at least a volume of the patient'sfleshy portions on the remaining limb that are to be displaced by thecompression regions. The relief/release regions can be enclosed orcompletely open provided there is minimal restriction to soft tissueflow.

In step 235, which is optional, one preferably will put on al sock orsleeve to facilitate donning by pulling the limb down into the socketmore completely.

Although the invention has been described using specific terms, devices,and/or methods, such description is for illustrative purposes of thepreferred embodiment(s) only. Changes may be made to the preferredembodiment(s) by those of ordinary skill in the art without departingfrom the scope of the present invention, which is set forth in thefollowing claims. In addition, it should be understood that aspects ofthe preferred embodiment(s) generally may be interchanged in whole or inpart.

1. A prosthetic device for use by a patient having a limb that has beenamputated and that has a longitudinal axis, wherein the prostheticdevice comprises: a first portion configured for placement on the limband having a plurality of compression portions and a plurality of reliefportions, wherein each of the plurality of compression portions iscomprised of a strut, wherein each of the plurality of relief portionsis a window disposed between two of the struts, wherein each of theplurality of compression portions is configured to compress a portion ofthe limb thereby causing excess portions of the limb to flow outwardlyat the plurality of relief portions, so that the excess portions of thelimb bulge outwardly without restriction through the windows and beyondthe first portion of the prosthetic device, wherein the plurality ofcompression portions is disposed circumferentially around the limb whenthe first portion of the prosthetic device is placed on the limb, andwherein each of the plurality of compression portions has a generallylongitudinal shape and is disposed longitudinally along a direction ofthe longitudinal axis of the limb when the first portion of theprosthetic device is placed on the limb.
 2. The prosthetic device ofclaim 1 wherein the limb has an outer circumference along an outersurface of the limb and has an at-rest radius measured from a centrallongitudinal axis of the limb, and wherein each of the plurality ofcompression portions is further configured to compress the portion ofthe limb so that the outer circumference of the limb is compressed to aradius that is reduced by at least thirty percent from the at-restradius of the limb and no more than seventy percent from the at-restradius.
 3. The prosthetic device of claim 1 wherein each strut isconstructed of a material that includes an acrylic laminate.
 4. Theprosthetic device of claim 1 wherein each strut is constructed of amaterial that includes an acrylic laminate with a stiffening memberconstructed of one of carbon fiber and para-aramid synthetic fiber. 5.The prosthetic device of claim 1 wherein the limb further has a longestbone having a length, and wherein each of the plurality of compressionportions extends for a length that is approximately equal to the lengthof the longest bone.
 6. The prosthetic device of claim 1 wherein thelimb further has a longest bone having a length, and wherein each of theplurality of compression portions extends for a length that is no lessthan approximately 80% of the length of the longest bone.
 7. Theprosthetic device of claim 1 wherein the prosthetic device is furtherfor use with a flexible membrane configured to encapsulate at least aportion of the limb of the patient, wherein the first portion of theprosthetic device is further configured for placement over the flexiblemembrane and on the limb when the at least the portion of the limb isencapsulated by the flexible membrane, and wherein portions of theflexible membrane are configured to bulge outwardly through the windowsalong with the excess portions of the limb in response to thecompressing of the portions of the limb.
 8. A prosthetic device for useby a patient having a limb that has been amputated and that has alongitudinal axis, wherein the prosthetic device comprises: an enclosureportion configured for placement on the limb and having a plurality ofcompression portions and a plurality of relief portions, wherein theplurality of compression portions and the plurality of relief portionsform at least a portion of an inner wall of the enclosure portion,wherein the inner wall is configured for encapsulating at least aportion of the limb when the enclosure portion is placed on the limb;wherein each of the plurality of compression portions is configured tocompress a portion of the limb thereby causing excess portions of thelimb to flow outwardly and into the plurality of relief portions, sothat the excess portions of the limb flow outwardly with essentially norestriction away from the plurality of compression portions, wherein theplurality of compression portions is disposed circumferentially aroundthe limb when the enclosure portion of the prosthetic device is on thelimb, wherein each of the plurality of compression portions has agenerally longitudinal shape and is disposed longitudinally along adirection of the longitudinal axis of the limb when the enclosureportion of the prosthetic device is on the limb, and wherein each of theplurality of relief portions has a generally longitudinal shape, isdisposed between two of the compression portions, and is disposedlongitudinally along the direction of the longitudinal axis of the limbwhen the enclosure portion of the prosthetic device is on the limb. 9.The prosthetic device of claim 8 wherein the limb further has a longestbone having a length, and wherein each of the plurality of compressionportions extends for a length that is approximately equal to the lengthof the longest bone.
 10. The prosthetic device of claim 8 wherein thelimb further has a longest bone having a length, and wherein each of theplurality of compression portions extends for a length that is no lessthan approximately 80% of the length of the longest bone.
 11. Theprosthetic device of claim 8 wherein the limb further has an outercircumference along an outer surface of the limb and has an at-restradius measured from a central longitudinal axis of the limb, andwherein each of the plurality of compression portions is furtherconfigured to compress the portion of the limb so that the outercircumference of the limb is compressed to a radius that is reduced byat least thirty percent from the at-rest radius of the limb and no morethan seventy percent from the at-rest radius.
 12. A method for using aprosthetic device comprising: placing an enclosure portion of theprosthetic device on a limb of a patient, wherein the limb has beenamputated and has a longitudinal axis, wherein the enclosure portion hasa plurality of compression portions and a plurality of relief portions,and wherein the plurality of compression portions and the plurality ofrelief portions form at least a portion of an inner wall of theenclosure portion, wherein the inner wall is configured forencapsulating at least a portion of the limb when the enclosure portionis placed on the limb; compressing portions of the limb using theplurality of compression portions; and causing excess portions of thelimb to flow outwardly and into the plurality of relief portions, sothat the excess portions of the limb flow outwardly with essentially norestriction away from the plurality of compression portions, wherein theplurality of compression portions is disposed circumferentially aroundthe limb when the enclosure portion of the prosthetic device is on thelimb, wherein each of the plurality of compression portions has agenerally longitudinal shape and is disposed longitudinally along adirection of the longitudinal axis of the limb when the enclosureportion of the prosthetic device is on the limb, and wherein each of theplurality of relief portions has a generally longitudinal shape, isdisposed between two of the compression portions, and is disposedlongitudinally along a direction of the longitudinal axis of the limbwhen the enclosure portion of the prosthetic device is on the limb. 13.The method of claim 12 wherein the limb further has a longest bonehaving a length, and wherein each of the plurality of compressionportions extends for a length that is approximately equal to the lengthof the longest bone.
 14. The method of claim 12 wherein the limb furtherhas a longest bone having a length, and wherein each of the plurality ofcompression portions extends for a length that is no less thanapproximately 80% of the length of the longest bone.
 15. The method ofclaim 12 wherein the limb further has an outer circumference along anouter surface of the limb and has an at-rest radius measured from acentral longitudinal axis of the limb, and wherein the compressing ofthe portions of the limb includes compressing the portions of the limbso that the outer circumference of the limb is compressed to a radiusthat is reduced by at least thirty percent from the at-rest radius ofthe limb and no more than seventy percent from the at-rest radius.
 16. Aprosthetic device for use by a patient having a limb that has beenamputated, wherein the limb has a longitudinal axis and has a bonegenerally extending along the longitudinal axis, wherein the prostheticdevice comprises: means for reducing relative movement of the bone inrelation to the prosthetic device when the prosthetic device is disposedon the limb and when the patient moves the limb; wherein the means forreducing the relative movement includes a plurality of compressionportions and a plurality of relief portions; wherein each of theplurality of compression portions has a generally longitudinal shape andis disposed longitudinally along a direction of the longitudinal axis ofthe limb when the prosthetic device is disposed on the limb, and whereineach of the plurality of relief portions has a generally longitudinalshape, is disposed between two of the compression portions, and isdisposed longitudinally along the direction of the longitudinal axis ofthe limb when the prosthetic device is disposed on the limb.
 17. Theprosthetic device of claim 16 wherein the bone of the limb has a lengthand is a longest bone of the limb, and wherein each of the plurality ofcompression portions extends for a length that is approximately equal tothe length of the bone.
 18. The prosthetic device of claim 16 whereinthe bone of the limb has a length and is a longest bone of the limb, andwherein each of the plurality of compression portions extends for alength that is no less than approximately 80% of the length of the bone.